The present invention relates to a device for fastening a seal to the end of a shaft to effect a seal between the shaft and the bore of a circular element encircling the shaft. The invention finds particular usage in gas-turbine engines to seal the area between a bore of a turbine wheel and an engine shaft passing through the wheel.
Presently, an O-ring or an annular seal with a square cross section is utilized in such installations and is maintained on the shaft by a pair of rings and a nut screwed onto a thread formed on the end of the shaft. However, this system requires additional locking means to lock the nut onto the shaft so as to prevent loosening of the seal. This system is also bulky, heavy and requires a thread to be formed on the shaft thereby increasing the manufacturing costs. When such a system is utilized on a gas-turbine engine shaft, in particular turbojet engines for aircraft, the fastening means must be carefully designed to assure reliable locking, thus increasing the design and manufacturing costs.
It is also known to hold the rings in place on the shaft by a circular spring clip which engages a groove formed on the shaft. This method of fastening is only suitable for relatively small diameter shafts and permits the rotation of the seal with respect to the shaft. This is impermissible on the shaft of a gas-turbine engine due to its increasing the wear of the seal and the possibility of producing undesirable vibrations during engine operation.